Various tasks require the application of intense light radiation to a limited or well-defined area of an object. An example, where the heat produced by the radiation does the job, is, in surgery, stopping hemorrhages by heat-coagulation of a bleeding blood vessel stump.
An example, were the quantum energy of the radiation is the important factor is dentistry, for hardening of polymeric matrix material of a tooth-filling or the like.
Work of the above identified type requires an apparatus which the user can manipulate by hand in a convenient and effortless manner and enables the user to apply the radiation quickly to the exact location where it is needed.
The known apparatus of this type do not meet these requirements for at least one of the following reasons:
The light source housing, which must provide for light and thermal shielding to avoid blinding and burning of the user is bulky.
More important, the light exit surface if brought into contact with the object to be heated, e.g. biological tissue, tends to stick to the object to be heated and becomes contaminated and therefore must be held in a safe distance from the object to be irradiated.
These difficulties greatly impair the ease of handling and make the known apparatus virtually useless for work of the above mentioned type.